Long long story - from experience - it runs better with 97. I find our DME over compensates when switch to 95 . Causing weird transmission shifts points. This will eventually smoothen out - until the next time you switch petrol.
So, from 2 years of ownership - I can tell you if you decide 97 - stick to it, 95 also stick to it. The moment you force the car to adapt, it gets all weird. Also, running outstation once in a while really sorts the car out.
FYI, the opinion above is personal - and not based on "feel" alone . I do monitor the adaptations value via INPA or ISTA.
The only way to sort out the "weird" shift points is to do a transmission adaptation reset via INPA and also to reset some DME adaptations value.